computor not recognizing fobs

Since I have kept fob in my left pocket the only time that it acted up is when I shifted my leg which then must block a signal and it would go back to fob 1 settings but the car has started every time so far. I think it is a range problem on the sensors but seeing as they have replaced every module and antenna that the fobs respond to I and the dealer do not know what will cure the problem Have been driving the car since april and settings have shifted only 4 times allmost livable